Question When we look back in time using Hubble or JWST?

[billslugg]

Here, maybe this will help:
"Conservation of energy doesn't apply to cosmology. General relativity doesn't have a conserved scalar mass-energy that can be defined in all spacetimes.[MTW] There is no standard way to define the total energy of the universe (regardless of whether the universe is spatially finite or infinite). There is not even any standard way to define the total mass-energy of the *observable* universe. There is no standard way to say whether or not mass-energy is conserved during cosmological expansion."

Reference: https://www.physicsforums.com/threads/what-is-the-total-mass-energy-of-the-universe.506985/

 

[Unclear Engineer]

Bill, your link basically says "We don't know!" It doesn't prove anything at all. It doesn't even agree that the universe is "closed" or "open", much less that the total of anything in it can be calculated.

So, let's look at other indicators. People who are proposing that "dark energy" is increasing because space is expanding are saying that dark energy does not obey the observed effects of expansion on the other, observed types of energy in space. The BBT explains the "temperature" of the universe decreasing by expansion lowering the energy density. The use of "red shift" bases its physical understanding on the concept that stretching space stretches the wave lengths of all photon in it, so that they are less energetic per unit size (wave length measurement).

So, all of our observations indicate that the types of energy that we can detect and measure do get reduced energy density as space expands. But, some people are proposing that dark energy, which we do not even have an explanation for, must be behaving differently than all of the other energy forms that we actually know something about, and somehow increase from nothing.

As people keep posting here, exceptional claims require exceptional proof - and this hypothesis has no proof at all. Just because you can think of something does not make it real. We have another thread going here on Space.com that proposes that "information" has mass, and that is what makes up the missing "dark matter".

It is possible to explain anything if all you have to do is make up new forces and substances that we can't detect that obey (conveniently) different rules than everything that we can detect. The trouble is that it is possible to make those unsupported explanations in many ways, so there is no basis for evaluating which one is true and which ones are false. Just because more people believe in one fairytale does not make that one true. We don't get to "vote-in" the physical laws that are most popular.

 

[Helio]

Helio, I did not say that Dark Energy does not exist (although I am not convinced that it does).

Yes, but my point is to help others understand that this isn't all that critical to the viability of the BBT. DE is something new to BBT and it is only needed as a way to "save the appearances" to at least put a label on whatever it is that explains acceleration of the expansion.

What I objected to was the postulate that it somehow is increasing as space expands, so that there is more total energy in the universe every second, and that is the reason that the rate of the universe's expansion is increasing.

The idea that there is more dark energy in the universe because there is more space in the universe is directly in conflict with the principle of conservation of energy + mass in the universe.

Agreed, it makes little sense, at least until we learn more, that density is somehow a constant.

But as Bill notes, it is tied to space, which doesn't decrease in density. Where does new space come from and how does it unfold so smoothly, etc.? GR may or may not handle this better than you or I suppose, but it would be nice to have some logical answers.

Do you actually believe that principle is wrong?

DE is too much a mystery to say how it does what it does, in apparent violation of thermo.

I will point out that the quantum foam, according to quantum calculations, argues that this foam has a value of 120 orders over what is observed, so perhaps it has a steady leak rate per unit volume. Of course, this is raw speculation on my part.

If the energy levels within the foam are somehow still extremely high, as was likely in the first Planck second, then these extremely short wavelength properties would allow much greater residency in the dimensions proposed in string theory (10, 11, or 26 dimensions). [Hooper addresses this a little as well. Great book!]

If so, what other principles of physics are you willing to agree are being violated by what we observe? How about the speed of light being constant everywhere for all time? How about gravity being constant with time?

The temperatures, per Hooper, during perhaps the end of the first Planck second were on the order of 10^29K. [Enlarging the LHC to that of the solar system would be required to reach those temperatures.] At those temperatures, quantum gravity theory argues that the four forces were far more equal, if not equal. So the universe was quite different then. As things quickly cooled, the forces became what we see today.

People seem to be unwilling to consider violations of even unprovable "laws" such as entropy could not decrease or that "information" cannot be lost or even hidden, no matter what happens inside a black hole.

What people are you talking about? Scientists?

 

[billslugg]

"Bill, your link basically says "We don't know!" - Unclear Engineer

Yes, you are correct. There is no conservation of energy in cosmology. It is entirely permissable to create something out of nothing in cosmology. Only on local scales in closed systems can conservation laws apply.

 

[Helio]

Bill, your link basically says "We don't know!" It doesn't prove anything at all. It doesn't even agree that the universe is "closed" or "open", much less that the total of anything in it can be calculated.

Theories are not proofs? Math has proofs, and the math has helped give credibility to some of the thousands of theories. There are, apparently, several thousand hypotheses for DM. Perhaps there are now over 100 on DE since it's been several years since I saw a report stating there were about two dozen hypotheses. [The author actually listed them by the names for those theories.]

So, let's look at other indicators. People who are proposing that "dark energy" is increasing because space is expanding are saying that dark energy does not obey the observed effects of expansion on the other, observed types of energy in space. The BBT explains the "temperature" of the universe decreasing by expansion lowering the energy density. The use of "red shift" bases its physical understanding on the concept that stretching space stretches the wave lengths of all photon in it, so that they are less energetic per unit size (wave length measurement).

Yes, but this is the residual energy we observe, via photons, that are traveling through space, so something like the foam is different, as I see it.

[I still am not convinced that photons actually get stretched during their travel since I would assume their intrinsic EM strength would not be influenced by the tiny incremental stretching of space. It was originally treated as a Doppler effect, which made sense.]

So, all of our observations indicate that the types of energy that we can detect and measure do get reduced energy density as space expands. But, some people are proposing that dark energy, which we do not even have an explanation for, must be behaving differently than all of the other energy forms that we actually know something about, and somehow increase from nothing.

Right. But, don't forget about Einstein's cosmological constant. GR does seem to have something to say about it.

It is possible to explain anything if all you have to do is make up new forces and substances that we can't detect that obey (conveniently) different rules than everything that we can detect.

Yes. This point is worth noting. When Galileo, for instance, falsified the Aristotle/Ptolemy/Thomist model, the competent Jesuits were quick to verify and agree with him. So they adopted the Tychonic model which does just what you state. But the inclusion of "fictious forces" never gave it any real credibility especially when compared the very elegant and unifying theory from Copernicus.

The trouble is that it is possible to make those unsupported explanations in many ways, so there is no basis for evaluating which one is true and which ones are false.

This is exactly why every hypothesis and theory must be falsifiable even in principle.

Just because more people believe in one fairytale does not make that one true. We don't get to "vote-in" the physical laws that are most popular.

Science that offers both predictions and is also falsifiable removes them from both Sillyville and Fairyland. That's why these two features are required.

But I agree that the number of people that agree (ie "consensus science") should not matter all that much. Scrutiny must be respected at all times. [This didn't happen related to Covid science, which is why I'm here, frankly. The CDC is now beginning to admit their short-comings. ]

 

[Unclear Engineer]

Trying to separate "dark energy" from "inflation" seems like an admission that even making one fairytale is not enough to explain the same phenomena in 2 different epochs of the same universe's history.

A "theory" that has as many untested "fitting" parameters as the Big Bang Theory simply loses respect of the critical thinkers. What makes it worse is the continuing statements that something "is" true or "did" happen, instead of a much more honest "I wonder if this could be true" or "did happen this way." Frankly, it is annoying to have "scientists" and "experts" expressing their musings as if they are proven, or even provable facts. It makes for popular media click bait, but it seems to be less than helpful for figuring out what is really causing the observations that we are making. Too much ego, not enough science in a lot of this.

 

[IG2007]

The following is not directed to anyone particular, but it is rather directed to everyone in general:

Can we please stop bashing on "scientists" and "experts"? They are not omniscient, they do not know everything - rather, they, like every proper scientist, first make observations, then make hypotheses to match that observation. And when the hypothesis gets enough observational backing, it becomes a theory. This is literally what we know as the scientific process, the only proper way of gathering information.

There is no room for fairytales in Science, every theory is based upon some observation. Yes, we can, and we should, debate about the theory - but we should not blame the people who came up with the theories, because they are merely doing their jobs. The thing about Dark Energy and Dark Matter is that they do not match with previous observations and theories, so we are merely trying to make new theories that can match both the new and the old at the same time. And the fact that we apply the name "Dark" to them is because we don't know a lot about them except the fact that they exist, or something like them exist, or otherwise we wouldn't see galaxies spinning around nor would we see almost every galaxy moving away from us. Dark Energy is one of the newest hot topics in Cosmology, and thus there are abundant amounts of hypotheses and theories and questions about its existence - and that is what should happen, and all of us are participating in it.

There is no need to personally blame scientists and physicists who have given their lives to the study of the aforementioned phenomena, but rather, we should make our own observations and theories and keep the scientific process alive and fresh.

 

[Unclear Engineer]

IG2007, since you seem to have quoted my previous post in several places, I am going to assume that those are the things that I should reply to.

First, I put "scientists" and "experts" in quotes because I do question just how scientific and expert the people being quoted in the popular media really are. The articles we see here on Space.com and elsewhere in the popular media seem to be more akin to "magic shows" than actual scientific explanations, which is the way the popular media works to get views to sell advertising. It isn't trying to be educational - it is trying to exploit the wow factor.

We readers rarely if ever get the chance to actually engage the people who develop the cosmological theories at a logical, scientific level. Even when in the same room with them, they too often take the attitude that they just don't have the time to teach us all they think we need to know to have a worthwhile conversation. So, the usual technique is to refer us to papers, which often don't really address what we want to talk about.

My experiences, where I actually try to talk as an expert about complex (but not cosmological) subjects with people who have no background in those subjects, is that it really requires me to understand what I think and what my basis is for thinking that. And I need to be able to explain it without jargon or reference to some document, somewhere. It is very difficult to do that. And, to be credible, I need to make sure that I keep my ego out of it and actually listen to the questions and concerns of the listeners. Being in "broadcast mode" all the time quickly becomes a credibility killer. I need to actually engage in the thought processes with the other parties.

We are not seeing that in the media articles on cosmology. And even pursuing the reference papers, we find the arguments that support a concept but are typically devoid of the counter arguments against it. Looking at the comments and questions and answers on papers and seminar presentations, I often see disagreements, but those are among the experts and clouded with jargon. And, egos are also very apparent in much of that give and take. Considering how much of an expert's credentials depend on the quantity of papers they have published, it is not surprising to me that egos are involved in these interactions.

So, in a forum like this, where there are repetitive articles and posts that use the tone that the BBT is accepted and should not be criticized by anybody who has not developed a better theory already, I do push back.

And, those push backs are aimed at the vulnerabilities in the thinking that supports the theory. Do I know that the theory is wrong? No. But I do know that its proponents have no way to know that it is right in many respects.

What I am seeing is, in my opinion, a severe lack of critical thinking and a strong desire to not have "the boat rocked". And, in forums like this, that mind set is not coming from the people who developed the theories, but from people who have studied those theories and can parrot them. So, this is more a debate between the believers and the skeptics from a big picture perspective, rather than a detailed assessment of the methods and execution of the theory development processes.

So, yes, I am "bashing" the thinking that well established physical laws like the conservation of energy and matter are not important in postulating how what we see can be occurring. And, I am bashing the simplistic thinking that something that completely violates those laws "must" have happened in a particular way because that is all that some theorist can think of, using present knowledge, that doesn't disrupt his theory.

I am willing to question whether some physical laws may have not been the same under far different circumstances. For instance, I question whether the entropy must increase in the subatomic plasma states, from which very specific isotopes of atoms coalesce when they are cooled. To me, that appears to be a clear example of order coming from chaos. But, others criticize my reasoning. It is OK with me if the criticism addresses my interpretation of the known facts - but not if it just criticizes my lack of respect for established laws of physics. So, when it comes to theorists extrapolating the observed red shifts in astronomy all the way back to where the whole universe is a single microscopic point, and then inventing a process called "inflation" that somehow violates the best cosmological theory we have (General Relativity) to get the universe to defy gravity and get out of a black hole, I don't seen any reason to treat that postulate with any more respect than others treat my thinking about how the law that entropy always must increase my not have applied under similar conditions.

To me, when people actually try to discuss seemingly unexplainable observations, it is important to do so in a very logical manner, with a clear distinction maintained between what we observe and what we are inferring. And, as theories develop and become more detailed and intricate, it is important to keep in mind how many steps each concept is away from the verifiable observations.

At this point in its development, the BBT is relying on a very large number of physical law defying assumptions for it to hang together at all. And, those assumptions don't seem to be getting questioned for their consistency with each other or their other potential implications that could disrupt the theory they are intended to support. To me, that is not the true scientific method. I seem to have started this concern when I pointed out that the BBT theorists keep introducing new, unconstrained parameters to explain new observations, and have now introduced 2 concepts that both involve expansion of the universe by completely unknown mechanisms, without seeming to feel any need for those 2 processes to be related in any way.

So, I am becoming more and more convinced that we are misinterpreting something profound about our astronomical observations, and pursuing a theory down a logical rabbit hole. I am making posts here on subjects that examine assumptions and inconsistencies, and, yes, I am critical of responses that dismiss my questions and points as simply being "explained" by the BBT, which actually is not explaining those things, but instead uses additional unconstrained fitting parameters every time a new observation does not fit with that theory.

On the other hand, I am also critical of the posts here that are purely metaphysical in their tone. The concept that "information" has mass is a good example. There seems to be no actual basis for that concept, beyond "Here are 2 things that we don't fully understand, so let's put them together and see if we can get a consistent explanation." As a start to a thought process, I don't have any problem with that type of broad thinking. I did the same thing myself in the thread that asked if dark matter could be a sea of regular matter with "negative energy" (which was actually suggested by Dirac decades ago as a source of "antiparticles"). The difference is that I am not claiming that is what dark matter must be - I am simply trying to discuss that concept using what we do observe and some logical inferences and, if we can devise them, tests of the concept's validity.

Can you see the difference between that thread and an article with the title "There is no dark matter. Instead, information has mass, physicist says" Link at https://bigthink.com/hard-science/dark-matter-theory/ . It contains this:

"In 1961, he predicted that erasing even one bit of information would release a tiny amount of heat, a figure which he calculated. Landauer said this proves information is more than just a mathematical quantity. This connects information to energy. Through experimental testing over the years, the Landauer Principle has held up."

So far as I see, that is an assertion, but where is the actual data and a discussion of its acquisition and interpretation to show that it has "held up"? Following the links, it seems that the experiment is actually yet to be done, and the person desiring to do the experiment is looking for support money.

So, my point is that I am willing to think broadly about potential new ideas, but I am insistent that the thought processes be logical and based on science so far as that can take it.

When it departs from that logical framework and is also asserted to be true (or at least accepted by "most people") is when I point out if it doesn't have any more scientific support than a fairytale.

 

[Catastrophe]

Unc, I certainly agree that we should examine, and be prepared to state and re-examine our assumptions. There is too much, imho, regurgitating old "theories", which may be no better than daydreams. In this, I also agree with you.

Cat

 

[RobbyQbit]

When we look back in time, we can see some of the most distant and oldest galaxies that have ever been observed. These galaxies are so far away that their light has taken billions of years to reach us. By looking at these galaxies, we can learn about the early Universe and how it has evolved over time.

The Hubble Space Telescope and the James Webb Space Telescope are two of the most powerful telescopes that have ever been built. These telescopes can see further into the Universe than any other telescope, and they have been used to discover some of the most distant and oldest galaxies.

The Hubble Space Telescope was launched in 1990 and it has been used to observe the Universe for over 25 years. The James Webb Space Telescope is scheduled to launch in 2021 and it will be even more powerful than Hubble.

These two telescopes have been used to study the most distant galaxies in the Universe. In 2016, astronomers used Hubble to study a galaxy that is 13.4 billion lightyears away from Earth. This galaxy is so far away that its light has taken over 13 billion years to reach us. This means that we are seeing this galaxy as it was over 13 billion years ago.

In 2018, astronomers used the James Webb Space Telescope to study a galaxy that is even more distant than the one observed by Hubble. This galaxy is so far away that its light has taken over 13.5 billion years to reach us.

This means that we are seeing this galaxy as it was over 13.5 billion years ago. These observations are important because they allow us to study the early Universe. By looking at these distant galaxies, we can learn about how the Universe has evolved over time.

I didn't think Hubble could look that far back given it's capturing Visible and UV wavelengths. I thought that's why JWST came in to look at the IR wavelengths. How do they achieve that?

 

[billslugg]

I didn't think Hubble could look that far back given it's capturing Visible and UV wavelengths. I thought that's why JWST came in to look at the IR wavelengths. How do they achieve that?

Hubble range is 0.1 micron to 2.5 microns.
JWST range is 0.6 micron to 28 microns.
Visible is 0.38 micron to 0.75 microns.
Both telescopes can see into the infra-red but JWST can see further.

 

[RobbyQbit]

Hubble range is 0.1 micron to 2.5 microns.
JWST range is 0.6 micron to 28 microns.
Visible is 0.38 micron to 0.75 microns.
Both telescopes can see into the infra-red but JWST can see further.

I always thought Hubble was in the UV/Visible. I stand corrected.